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One of the problems with this stupid name "Big Bang" is that it really doesn't describe anything that legitimate cosmologists and astrophysicists study about the early universe. The common conception of the "Big Bang" (which was a term of derision coined by one of its early critics, Fred Hoyle) is that it says the early universe started as a point where all matter was compressed, and then that matter expanded out in a giant explosion into the surrounding space, spreading out until it reached the state it is today. That's not what the evolution of the universe looks like. Instead, the better understanding is that initially the Universe was in a "hot dense state", which is to say that all of the matter was packed together very closely, and that the space that contained the matter expanded rapidly from this initial hot dense state through a period known as the Inflationary epoch, to reach the universe roughly like what we see today, which still continues to expand. The thing to wrap one's head around is that 1) the universe is not expanding into more space, it is merely becoming less dense (to understand how this can work, David Hilbert's infinite hotel is a nice thought experiment), so that, on the largest scales, the matter is all moving further apart from other matter. There is no perspective from which to view this "from the outside". Imagine a world where everything around you is superhot, super dense matter and then imagine that matter spreading out in all directions. The perspective on this expansion is the same regardless of where you are in the universe. The universe can even be infinite and still expand in the same way. That notion that the universe is becoming less dense and cooler is, in some senses, the "Big Bang". There is a point where our models like quantum mechanics and general relativity and the like can't actually predict what the universe behaved like, anything earlier than the time when the models break down is called the "singularity", which people again don't know what it means. A singularity is not a point (as some imagine it to mean); a singularity means, quite literally, "a place where the mathematics of the model doesn't work anymore". That's it. It's a barrier that our current means of extrapolating knowledge can't penetrate. It just means that at some point, matter becomes so hot and so dense that its behavior can't be predicted by current models. Data from the James Webb telescope is expected to refine this model of the evolution of the universe, in the sense that it is expected to give us better data to correct some false assumptions, or narrow the error bars on measurements we've already made, but it's not going to "debunk" anything, certainly not anything as well-supported by the evidence than our models of the early part of the universe (for lack of a better term, of the "Big Bang"). All of the things we understand in a broad sense (hot dense early universe, metric expansion, etc.) aren't going anywhere, because these things all match data very well, certainly better than any competing models. The JWST is going to be revolutionary in providing us with data we've never had before to refine these models and to learn better about what these time periods looked like, and how they actually evolved, but the existing data won't simply stop existing because the JWST finds more data. --Jayron3219:07, 24 August 2022 (UTC)[reply]
That very misconception of the Big Bang seems to be exemplified by the following sentence:
It may seem counter-intuitive that an infinite and yet infinitely dense universe could be created in a single instant at the Big Bang when R=0, but exactly that is predicted mathematically when k does not equal 1.
Also relevant is that we don't need it to happen again. It only has to have happened only once to have gotten us where we are today. We know that it did happen, because we're here now. That it is fantastically unlikely to happen again is irrelevant. Also, also relevant is that we don't know what happened at times earlier than when our model reaches the singularity state. Like, it's a complete black box before that. We don't know in any way what the universe behaved like, how long it existed, what it was doing before that point, etc. There's lots of wild-ass speculation, but none of it is based on any predictions that can be made from actual observations and valid mathematics. --Jayron3212:17, 26 August 2022 (UTC)[reply]
It is IMO a curious use of language to say that we don't need the universe existing to happen again because the universe existing has happened. (We also do not need 2 plus 2 to happen being 4 again, because this having happened only once suffices.) God knows, maybe the universe has always existed. I think, though, that as long as we need anything at all, we need the universe existing to continue to happen. --Lambiam08:55, 30 August 2022 (UTC)[reply]
The Institute of Art and Ideas is an organization that's mission is to promote fringe and not-widely-accepted theories and concepts. It's fine that they exist, but their events are not evidence of a valid scientific consensus on a topic. --Jayron3212:52, 1 September 2022 (UTC)[reply]
meta discussion
The following discussion has been closed. Please do not modify it.
Existing is not sufficient for assessing validity. His criticism certainly exists, but I don't know where it meets any other criteria of validity. --Jayron3213:14, 1 September 2022 (UTC)[reply]
This is not a venue for asserting opinions or debate. But since Lerner's observations and views are certainly relevant to the OP's question I provided the link for context. Modocc (talk) 13:29, 1 September 2022 (UTC)[reply]
What makes Lerner's views relevant? Other than he made them public, so we know they exist, that doesn't make them relevant. I can publish my views on anything, what makes my views relevant? --Jayron3214:35, 1 September 2022 (UTC)[reply]
You did exactly that; you recommended that someone read Lerner's perspective, as though it had the same validity as all of the rest of established science and then doubled down when you said that his work was potentially valid. The new data will be dealt with in good time, and we'll deal with that as it comes up; but the new data is not refuting established models, it is refining them. The basic outline of existing cosmology is not being debunked or refuted, merely updated and refined. --Jayron3216:06, 1 September 2022 (UTC)[reply]
Providing context and links is what we do here. We are not supposed to be shoveling out and upholding only our own opinions, biases, dogma, crack-pottery, the consensus and nothing else, etc. It's possible the data (or lack there of) will eventually be resolved with a paradigm shift and not merely "refined". And I did not put Lerner's view on "equal footing". Modocc (talk) 16:25, 1 September 2022 (UTC)[reply]
We're supposed to be providing valid context and links. Providing links to blatant crackpottery (and again, not my assessment that his work is batshit, that's the general consensus of people who actually study astrophysics. My opinion is irrelevant here) is not what we do, it implies that it might be useful to help the OP learn things that may help answer their question; it does not. To give Lerner's view any visibility is to grant it undue weight. When someone asks about vaccines, we don't send them to information published by Andrew Wakefield and say "here's an alternative viewpoint. Check it out and decide for yourself." When someone asks "how did the Pyramids get built" we don't send them to Graham Hancock or Erich von Daniken. Same here. --Jayron3218:03, 1 September 2022 (UTC)[reply]
That is wise and ethical, especially with regard to referencing knowledge regarding our daily lives. As for cosmology, historically there have been many disputed paradigm shifts and the participants within these debates are fallible. So can we leave this discusion at that? I'm closing it but feel free to add to it. Modocc (talk) 18:40, 1 September 2022 (UTC)[reply]
